Creating Transitopolis

The City vs. Country mismatch (where we plan for transportation systems seemingly independent of the context: city or country (suburb)) is especially relevant in metropolitan areas constructing expensive medium and high capacity transit lines to presently undeveloped places, or (re-)constructing and widening freeways in the midst of core cities.

If we are building a city, that means focusing resources closer to the center than the edges, since that is where more of the growth will be.

So the question arises in Minnesota: Are we building a city in the Minneapolis-St. Paul region or not?

Some would argue the region is already a city. Clearly the downtowns and some nearby areas resemble cities. But much if not most of the population lives in single family homes with a yard. Not there is anything wrong with that, but that yard increases spacing between neighbors, lowers densities, and makes it harder to operate a successful transit system in the automobile era.

The decisions we make regarding transportation investment rest on what our collective vision is for this place. If we are building a city, going “all in” on transit is a lot more sensible than if we are not, and a lot more sensible than half-measures. If we are not, going even partly in on fixed rail transit is fairly pointless.

The evidence to date is fairly mixed. The region is growing at about 1 percent or so per year in population. That is a bit under 30,000 people or so per year. (Investing in transit will not put a measurable dent on this, as it is hard to imagine it either increasing or decreasing the birth or death rate noticeably or significantly affecting migration patterns).

Where are those people going? Most of them are not being added to the center. If all of them were added to Minneapolis and St. Paul proper, the populations of the core cities would rise from 667,000 in 2010 to about 950,000 in 2020. If more than half of them were added to the core cities, their population would be around 810,000. Current forecasts suggest the population of the core will be closer to 732,000. In other words, well more than half (around 80%) of the region’s growth remains outside the core cities, and not terribly urban. While the center is projected to grow at a faster rate than the edges, it is not growing faster in absolute numbers.

This region collectively much more resembles Broadacre City than Greenwich Village, and probably more Broadacre City than even Welwyn Garden City or Letchworth. While the density at the edges after development must (by definition) be higher than before development, the average experienced density (e.g. the population-weighted density) may continue to fall as the region expands.

In this dispersed suburban landscape, point-to-point transportation predominates.

In the not-quite-a-city urban areas, point-to-point transportation still predominates.

It is only in full-fledged dense cities (the level of density required depends on income, technology, and other factors), and dense cities that sustain, that full-fledged dense (fixed route, fixed infrastructure) transit is warranted. Loosely, the transit-city threshold is on the order of 10,000 persons per square mile, sustained over some region. This implies a Minneapolis population of 540,000 and a St. Paul population of 520,000. While those numbers are achievable in principle, they require significant changes in market demand and reduction in supply constraints to achieve. If it were to be achieved, still under 1/3 of the region would be in the transit city. The remainder would be the country, or its suburban simulacrum.

Certainly, some parts of the core cities already sustain this density, and there is no requirement that all of the core city achieves the density, just that a sufficiently large part does. Most doesn’t.

For the Metropolitan area, fixing the total space, this threshold implies a population of 63 million, or relaxing the space but fixing the  population, a shrinkage to a developed area of 345 square miles. I would consider either outcome highly unlikely.

The car-free lifestyle is sufficiently uncommon that the local newspaper does a feature on it.

In less dense cities, less transit is warranted. But if the transit is insufficiently dense (in space (coverage) and time (frequency)), anyone with a choice will anchor to the on-demand, point-to-point mode, which will be sufficiently faster to outweigh any additional expense


Creating Transitopolis: the Transit City

Positive (and Negative) Feedbacks in Transportation
Positive (and Negative) Feedbacks in Transportation

Building the transit city (Transit-opolis) requires most of  the region’s central city residents (20% today) to willingly abandon the automobile in the first place: creating an environment where car ownership can be voluntarily foregone because it is to the benefit of all concerned not to own the car. The more transit users there are, the better the transit service is, in a virtuous cycle. (And of course, the fewer transit users there are, the worse the service, in a vicious cycle).

This implies focusing transit investments in the central cities, and not diffusing scarce capital like peanut butter across the region.

Why can’t we have the best of both worlds? There are a variety of interim or transitional strategies

  1. Park and ride lots accessed by private car may serve  the center-working/surburban-living suburbanite, which transfer the worker to a radial transit route. This serves a small fraction of workers, since most people don’t work downtown, where these radial services terminate, and the frequencies are typically not high enough (especially mid-day) to rely on for anyone with irregularity in their life.
  2. Single Car households  with multiple workers splits the difference, where presumably at least one of the workers does not use a car for travel to work, or the two workers carpool to the same location. This is certainly the most common hybrid case.
  3. Weekend Car households  in which the work trip is conducted by walking, biking, or transit, and the car is used for the weekend and special trips.
  4. Car sharing (on-demand car rental) allows the car-less transit user to have a car when needed for the less frequent trips. Taxis (and so-called ride-sharing services) serve a similar function.

These attempts at melding can serve specific niches and are potential transitional steps to the transit city, in that it is more likely to give up a car for some trips than all trips, or portions of trips than all of the trip. They are not however the end state.


 Like Clue, Pick your ending


My own prediction is that we are not in fact building a transit city. The densities that will emerge in Minneapolis and St. Paul in the next 20 or 30 years are insufficient to support a transit-based city for a majority of residents of even the core cities. (And, simultaneously and not coincidentally, the transit investments are insufficient to support a city where most people are car-less).

Pale Probiscidea
Pale Probiscidea

This explains my pessimism about the use of expensive (high fixed cost) city transit tools now. The right decision if you are certain you are building a transit city (or already live in one) is different from the decision if you are not.

While it is argued that never making the investments will ensure the transit city does not emerge, we can continuously ratchet up, rather than doing it in enormous steps. Not investing now does not mean never investing. “No” is reversible (in other words, “no” does not mean “no”).

On the other hand, “yes” is irreversible for a long time. But making the investment does not guarantee the transit city will emerge, plenty of cities, including our own, have invested in rail without seeing accompanying development, leaving an enormous pale proboscidea in its place.

Alternative Ending

My own prediction is that the core cities of Minneapolis and St. Paul are on a path towards Transitopolis. The necessary population densities to support transit are within striking distance, especially in Minneapolis, and the leadership of both cities is keen on achieving that. The big question is whether the demand for higher density housing is there in the cities, and with changing demographics, preferences, and technologies, the demand for suburban lifestyle is diminishing relative to that for urban living. Most people won’t spend their entire lives in either suburban harmony or at an urban tempo, but rather migrate between the two over the years.

The investments in the cities to support transit at a level that most people can avoid the car for most trips are still too low to make this work, there is a marked lack of ambition on the part of regional transportation officials to serve the transit cities they are building with actual rapid transit. This dysfunction has several causes, not the least of which is the leadership of planning organizations that don’t use the modes they manage, which we can attribute to the strange politics of regional organizations.